• 경영과학
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• 제19권1호
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• pp.1-12
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• 2002

Performances of common zone with various sizes are examined for possible demand rate variations for an AS/RS. Common zone is a middle area located between the 1st class and the 2nd class to be used by the 1st class Items if the assigned racks are not enough. This area is designed to resolve the rack shortage problem associated with a particular class. In the previous researches, effect of demand rate variation is Ignored since flxed demand rate is assumed. It is found that rack shortage rate is decreased up to 67% of common zone size. However, no difference is found at above 70%. Waiting time tends to be longer with Increased common zone while travel time and throughput are not affected at all with the common zone sloe.

• 산업경영시스템학회지
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• 제35권4호
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• pp.110-117
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• 2012

The demand for facility used in producing multi-products is changed dynamically for discrete and finite time periods. The excess or the shortage for facility is occurred according to difference of the facility capacity size and demand for facility through given time periods. The shortage facility is met through the outsourcing production. The excess facility cost is considered for the periods that the facility capacity is greater than the demand for the facility, and the outsourcing production cost is considered for the periods that the demand for facility is greater than the facility capacity. This paper addresses to determine the facility capacity size, outsourcing production products and amount that minimizes the sum of the facility capacity cost, the excess facility cost and the outsourcing production cost. The characteristics of the optimal solution are analyzed, and an algorithm applying them is developed. A numerical example is shown to explain the problem.

• 한국항만경제학회지
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• 제21권3호
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• pp.83-113
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• 2005

In this study, for purpose of searching for measures to lower the logistics costs which is one of the most difficulties for the small-medium sized manufacturers in Pusan and Kimhae, those manufacturers were surveyed with questionnaire about the facts in the export logistics costs, difficulties related to the costs, and measures they thought for lowering the cost. Taking account of findings from the survey, the comprehensive measures of saving the export logistics costs were to be proposed. In the surveyed manufacturers, the problems they thought over export logistics costs lied in short logistics information and transportation-related difficulties in cargo and distribution, insufficient standardization in packaging and the shortage of material handling equipments in unloading. In transportation, frequent non-fulfillment of in-time shipment, cost increase including over consumption of transportation time due to traffic jam, and the biased heavy use of inland transportation were pointed out as problems. In customs clearance, logistics information, and marine insurance, addressed were complexity in custom clearance and bonded transportation procedures, and the shortage of software and hardware to construct logistics information system.

• 한국수자원학회논문집
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• 제55권2호
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• pp.121-133
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• 2022

기상학적으로 예년 대비 부족한 강우량으로 인해 발생하는 가뭄재해는 피해범위가 광범위하고, 그 발생과 소멸을 쉽게 파악하기 어려운 특징을 가지고 있다. 그렇기 때문에 가뭄 발생예상 지역과 그 물부족량을 신뢰성 있고, 신속하게 예측하는 것은 가뭄 대응체계 구축에서 중요한 요소이다. 하지만, 현재는 과거 약 50여년의 기상관측자료로 그 경우의 수가 제한된다는 문제점이 있다. 그렇기 때문에 과거에 발생한 가뭄과 양상이 다른 경우 가뭄으로 인한 물부족량을 예측하기 어려운 한계점이 있다. 이러한 문제 해결을 위해 본 연구에서는 4개 RCP 시나리오 자료를 물수지 분석 모형에 적용하여 360개년의 연간 물부족량을 산출하였다. 다음으로 다층신경망 모형의 입력값으로 RCP 시나리오로부터 산출된 SPEI 값을 그리고, 출력값으로 연간 물부족량을 적용하여 학습을 진행했다. 학습된 모형을 통해 과거 수 개월 동안의 SPEI값과 미래 예측되는 가뭄 상황을 입력함으로써 쉽고 신뢰성 있게 중권역별 예상 물부족량을 산정할 수 있다. 이는 의사결정자들이 가뭄 발생 이전에 효율적인 가뭄 대응책 수립에 도움이 될 것으로 판단된다.

• 대한지역사회영양학회지
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• 제6권3호
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• pp.371-379
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• 2001

The present study was conducted to determine whether the food shortage situation in North Korea has affected its people differentially according to social class. We performed a literature search on North Korean books and documents on food and nutrition. We also conducted a mail survey on North Korean defectors to estimate the energy and nutrient intake and the practice of foraging for wild foods at the time of food crisis in North Korea. The subjects were 150 adults, 104 men and 46 women, aged 20 years and older, who resettled in the South Korea after the food crisis. The mean energy intakes for men and women were estimated to be 1,260 kcal and 980.6 kcal, respectively, which were far less than 2,900 kcal and 2,600 kcal, the intake levels recommended for North Korean men and women, respectively. Thirty seven percent of the subjects reported a lack of foods adequate enough for work and other daily activities, and fifty seven percent reported a routine use of wild foods such as roots, grass, stalks, and tree bark with an average of 4 items per day. Food consumption patterns on a typical day were different by social classes with the high class people consuming an affluent diet in the midst of a severe food shortage.

• Journal of Nutrition and Health
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• 제33권5호
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• pp.540-547
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• 2000

The present study was conducted to document North Korea's long standing food shortage situation and to evaluate the devastating effects of its recent food crisis on the already poor health and nutritional state of the people in North Korea. We analyzed the mail survey data on food consumption patterns and anthropometry of 109 North Korean defectors, male, aged 20 years and older, who resettled in the South during the period of 1988-1999. The result of our survey data indicated that during 1988-1993 when North Korea's food supply was not yet emerged as a serious problem, food and nutrient intake of North Korean defectors was estimated to be significantly lower that the recommended intake levels for maintenance. Energy and protein intake of subjects who defected further with the recent food crisis. For subjects who defected after 1994, the total and animal food intakes were reduced to 67% and 25%, respectively, of the amounts consumed by those who defected in the period of 1988-1993, and their energy and protein intake was decreased by 27% and 30% to the level of 1,181kcal and 40g. Regardless of the time of defection, the mean height and body weight of defectors was significantly lower than that of South Korean reference men. The prevalence of infectious diseases and malnutrition signs was higher among defectors who resettled in the South after 1994 compared to those who resettled during 1988-1993.

• 산업경영시스템학회지
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• 제37권3호
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• pp.8-15
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• 2014

For zero inventory and mixed assembly production, JIT (Just In Time) production system in Toyota and JIS (Just-In-Sequence) production system in Hyundai motor co. have been proposed in automobile production areas. Even though the production systems are popular in the areas, many subcontract companies producing part-modules for final production at a parent company suffers from excessive or shortage amount of inventory due to the time gap of production and delivery to the parent company. In this study, we propose an efficient real-time assembly sequence system applying a well-known Pareto method using Paint-In information in painting process and daily production planning information. Based on this system, a production line can estimate the shortage amount of UPH (Units Per Hour) at production line and recovers the amount before operating assembly production in the line. The proposed system provides efficiency on productivity compared with the previous system.

• 한국환경교육학회지:환경교육
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• 제12권1호
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• pp.391-409
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• 1999

From the students' point of view, this study was carried out to find out barriers to environmental conservation practice of secondary school students. According to the questionare and interview with secondary school students on barriers to environmental conservation practice at home, school, society and fellow-relation conditions and in personal psychology, the following findings were resulted. The major barriers to environmental conservation practice are (1) not doing environmental conservation practice of parents, friends and neighborhood, (2) having no interest in environment and environmental problems, (3) dirty and laboriousness of environmental conservation practice, (4) lack of environmental equipments, (5) the shortage of chance and time for environmental conversation practice, (6) lack of the inducement for environmental conservaton from school, (7) little effects of individual environmental practice, (8) a busy life, (9) shortage of the voluntary courage to practice for environmental conservation, (10) lack of compensation on the environmental conservation practice, (11) anti-environmental behavior among friends, (12) urging on edcation of parents. Those barriers related with home, school, society and fellow-relation anti-environmental conditions hold back environmental conservation practice of secondary school students. Those barriers are divided into three closely correlated tipes, (1) unpleasant traits of environmental conservation practice such as cleaning, recycling were linked with personal psychology, (2) lack of the social interest and practice for environmental conservation were linked with personal psychology, (3) the social atmosphere to urge on education was linked with students' busy life and the shortage of chance and time for environmental conversation practice. According to the results, attractive environmental education programs, home environmental education, cooperative environmental conservation programs, and inducements for environmental conservation are reguired of secondary school students to promote environmental conservation practice.

• International Journal of Reliability and Applications
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• 제5권2호
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• pp.75-80
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• 2004

Relationships between inventory policy and operational availability of military equipment maintained under a logistics support system are analyzed. A continuous review inventory model with a stochastic demand typically used in a military logistics support is considered and some numerical studies are provided.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 봄 학술발표회 논문집
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• pp.12-15
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• 1993

Critical shortage of natural aggregate for production of concrete is developing in many urban area. At the same time increasing quantities of demolished concrete form deteriorated and obsolete structures are generated as a waste material in the same areas. The reuse of a waste concrete may settle the problems of environmental pollution and shortage of adquate aggregate, Therefore, this study is to reuse a waste concrete as aggregate for concrete, It is the purpose of this present study to investigate and analyze how the addition rates of superplasticizer and curing condition affect the properties of fresh and hardened recycled aggregate concrete comparing with those of ordinary concrete and crushed stone concrete.